This application requests funds for the preparation and assay of collected biological samples in order to prepare for subsequent investigation of the links between infection, inflammation, immune function, metabolic indicators, hormonal levels, genetic factors, and indicators of additional physiological processes and health outcomes from early childhood through old age among the Tsimane of Bolivia. The use of data for a population with a low life expectancy and an epidemiological environment reflecting historical conditions experienced in the United States and Europe more than a century ago will allow us to read history sideways and evaluate hypotheses relating environmental conditions to biological processes across a broad set of integrated physiological systems. A broad aim of this investigation is to advance theory on the biodemography of the human life course, with a specific focus on aging and the lifespan. The biological theory underlying this investigation links aging to synergies between nutrition and inflammation and their role in oxidative stress, somatic repair and growth. The population studied provides the opportunity to examine empirical evidence that addresses theories linking energy allocation strategies relevant to the evolution of the human lifespan in a highly infectious environment. Data for the Tsimane come from an ongoing multiwave anthropological study that has collected unanalyzed frozen samples of blood serum, plasma, leukocytes, and urine. Pilot analysis has indicated ability to collect, store in the field, and transport biological samples. Some of these frozen samples have been stored since 2004 and there is a need for assay before they degrade. Biological samples will be assayed from approximately 1700 individuals, about 400 of whom are over the age of 40. Some of these assays will be done across all ages and only one time, e.g. genetic markers, to indicate age-specific population levels of markers. Other assays will be age-specific and some will be done from samples collected from the same individuals at multiple time points. These will generally be for the sample 40 years of age and over to examine individual stability in the marker (generally at 3 time points), to examine change with age (over 4 years of time), and to link change over time in one biological indicator to changes in others or to other physiological, demographic and environmental conditions. The indicators produced in this project will allow us to test novel hypotheses about the distribution of physiological resources to growth and repair, activity, and reproduction in a unique epidemiological setting. The project is exploratory in a number of ways: the setting is unique in its epidemiological conditions;some of the assays are used to identify biological characteristics across the full range of ages which is not well-known for this or any other population;a small number of the assays are exploratory in this population;the theoretical models that will be tested with the data provided by these assays will add significantly to our understanding of past, current, and future physiological aging. PUBLIC HEALTH RELEVANCE: The proposed project will provide information to better understand the world in which we evolved, a world of infection and scarce nutrition resources. The work carried out with the data produced through this project will allow us to assess how conditions in the modern world, with little exposure to infection and extensive resources, may result in adverse conditions for an aging population such as obesity and overnutrition. Results of this project will lead us to better understand the role of worldwide declines in infection throughout life in causing changes in the rate of aging in later life.